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(CNN) -- When are wildfires a good thing? Maybe more often than you think.

Fires have served Mother Nature dutifully for millennia, shaping the landscape, revitalizing forests and grasslands, clearing out underbrush and weeding out weak trees. But Americans have traditionally viewed such blazes as a menace, prompting strict suppression policies.

Today, amid near-universal accord on the need to protect communities and preserve forests, many experts have developed a new appreciation for wildfires' historic and vital role in nature. But the preservative value of fire may be hard to explain to a family that built its dream home on a forest's edge or tourists who see their favorite hiking trail or campground under threat.

"It's too late to ask everyone to leave," said Tom Scott, a wildlife specialist based at the University of California, Riverside. "But wildfires are not always a catastrophe because they're guaranteed to happen."

Elite "hot shot" crews, smoke jumpers and other firefighters have been inordinately busy in the past several years, said Michael Apicello of the National Interagency Fire Center, or NIFC, the U.S. hub for communicating, distributing resources and dispatching manpower when major blazes break out.

As development infringes more and more on wild lands, the number of homes damaged in wildfires has doubled in the past decade to at least 2,600 annually, Scott said.

Firefighters' success could worsen the problem, some warn, as dousing small, low-intensity blazes -- which clear out brush and other flammable ground-level material -- may increase the likelihood of large conflagrations later.

"Putting out fires is like repeatedly applying Band-Aids," said Laura McCarthy, policy director at the Forest Guild, a nonprofit group of practicing foresters that promotes research and programs. "Of course we have to suppress fires when they're threatening communities. But it's a Catch-22 -- we are in a self-perpetuating cycle."

Fiery history

Wildfires have long affected the look, function and dynamic of nature, including how plants, animals, insects and microorganisms interact, said Colorado State University professor Phil Omi.

"Fire has occurred over eons in fire-adapted ecosystems," Apicello said. "Many forest types have developed with fire and, a lot of times, fire has acted as a cleansing agent" by eliminating dead underbrush, weak or diseased organisms, and more.

That process continued largely unabated in the United States until 1910, when huge blazes wiped out communities in Michigan and Wisconsin.

"Out of that came the reasoning that all fires were bad, and we have to put them out," Apicello said.

Twenty-five years later, the government adopted the so-called 10 a.m. policy, a mandate that all available resources be used to quell a fire by 10 on the morning after it erupted.

Still, much of America's forest land remained uninhabited, unvisited, and thus undisturbed. But that changed as the 20th century progressed, with new and improved roads plus unremitting development bringing humans in closer contact with wild lands.

The 2000 fire season, which included a blaze dangerously close to the nuclear lab at Los Alamos, New Mexico, served as a "wake-up call that we needed to do something about fuels, so forest health and resiliency is a priority," said Apicello, a former smoke jumper who said many once-remote areas in which he fought fires during the 1970s are now developed.

Climate matters

Although wildfires do flare in the South, the Midwest and elsewhere, most occur west of the Mississippi River in areas known for their generally dry and hot summer months.

"In the eastern deciduous forests that get a lot of rainfall in the summer, you get a lot of decomposition. But nothing rots out West," Scott said. "You have dry [fuel], and it accumulates. One way to recycle it is to burn it."

Persistent drought and heat waves have exacerbated the problem in recent years.

"It's sometimes all too easy to point the finger at human activity," Omi said. "But [the increase in fires] may be as much due to climate as to what humans have done."

Experts say humans are more likely to cause fires (by campfires or arson) in more populated areas like California, while natural causes like lightning are more common in remote regions. In sum, people start more than four out of every five wildfires, according to FEMA.

One problem is what sparks a fire, but perhaps more important is a blaze's severity and longevity. A forest with more and drier "fuel" (roughly translated, anything flammable) is more likely to have a large blaze than one in which smaller, calmer fires have cleared out the underbrush.

"If the fire cycle gets interrupted, dense fuels that don't get consumed [in smaller, cooler fires] flare up, and you get burns on a larger scale, with higher intensity," Scott said. "We probably have made it worse: We can put out the easy fires, but we cannot [as easily] put out the bad ones."

'A paramilitary organization'

Authorities employ many techniques and tools on the ground and in the air to suppress wildfires.

When a large conflagration erupts -- the worst, "crown fires," in which a blaze jumps from tree to tree, are often fueled by strong winds -- authorities closest to the scene respond immediately as the NIFC coordinates activities from afar.

"The management of that incident becomes a paramilitary organization," said Omi, who fought wildfires for four years in the Pacific Northwest. "It's a fairly complex and sometimes a fairly lucrative endeavor for contractors, and it's also dangerous."

About 600 smoke jumpers, based at nine Bureau of Land Management and National Forest Service sites, can be over and at a fire within minutes of its being spotted.

Apicello described his former cohorts as "initial attack, rapid-response resources deployed to remote fires when they are small, to prevent them from becoming large. They like to get them in, put the fire out, and not keep them there for long, so they can go on to the next fire."

Larger teams of firefighters, drawn mostly from nearby communities and the NFS ranks, often join these teams, as well as elite "hot shot" crews thrust on the front lines. Air tankers and helicopters typically drop flame retardants from above, while firefighters below use axes, shovels and, if possible, water hoses to sap fuel, heat or oxygen and quell the blaze.

"The technologies have much improved, [and] the way they manage the forest is far more enlightened," Omi said. "But we're fooling ourselves if we believe that we've had much of an impact in terms of controlling costs and losses from wildfires."

Forest experts stress the need for public education, so that residents moving into potentially perilous areas know about the weather, vegetation and historic significance of wildfires.

"We can live in these places, but we ought to understand that some risk goes along with it," Scott said. "People are finding ways to live with fire. [Fighting wildfires] is not a battle to be fought, it's a storm to be weathered."